Oxygen supply control mechanism



Jan. 20, 1942. P. F. MEYN OXYGEN SUPPLY CONTROL MECHANISM I Filed May 8;1940 l iNQ ENTOE PaaZ F/Vqg/z.

Illlllllllfllllllll I: rfllllrrlrlr Patented Jan. 20, 1942 UNITED STATESPATENT OFFICE OXYGEN SUPPLY CONTROL MECHANISM- Paul F. Meyn, Chicago,Ill.,' assignor to The Gaertner SclentiflcCorporation, Chicago, 111., acorporation of Illinois Application May 3,1940, Serial No. 333,934 I Thepresent invention relates to an improved type of apparatus for theautomatic control of the oxygen supply of a respiration system designedfor use in airplanes at high altitudes.

In the control of an oxygen supply for respiratory purposes at highaltitudes where the natural content of the oxygen in the air isinsufllcient for respiratory needs the quantity of oxygen will dependupon the altitude but the dependence is not necessarily a directrelationship,

and a principal object of the present invention is the provision of animproved type of automatic oxygen supply control apparatus which will.provide the proper supply of oxygen to meet with individual needsregardless of altitude and to further provide for the supply of thisquantity of oxygen to any particular number of users'from a. singlesource.

A further object of the inventionis to provide oxygen supply controlequipment which operates in part in accordance with the altitude and in.part'in accordance with the amount of oxygen being consumed, or, inother words, in accordance with the number of persons usingthe oxygensupply at any particular time.

An additional object is the provision of oxygen supply control equipmenthaving a primary actuating mechanism independent of atmospheric pressureto provide in the oxygen supply manifold a substantially constantabsolute pressure regardless of the altitude or the number of users fromthe supply manifold and a secondary actuating mechanism responsive toaltitude changes for augmenting the supply of oxygen provided by theprimary actuating mechanism by varying the absolute pressure in thesupply manifold in accordance with altitude changes.

These and other objects will be observed upon consideration of thefollowing specification and by reference tothe accompanying drawing, inwhich:

Fig. 1 is a bottom view of the apparatus shown in Fig. 3;

Fig. 2 is Fi 3;

Fig. 3 is a sectional view taken along line H of Fig. 1; and

Fig. 4 is a fragmentary sectional view taken along line 4-4 of'Fig. 1. vIn the apparatus shown in the drawing the housing It has communicatingwith it the supa top View of thefapparatus shown in 4 Claims. (Cl.137-153) seat I! is depresseddownwardly, oxygen is free to pass throughthe channel l2and the port It.

The internal frame member in which the valve structure is housedprovides an upper compartment 2| and a lower compartment 22. The upperportion of compartment 2| is closed by a flexible diaphragm 23 which ismaintained in position by the cap 24, the latter being screwed about thehousing Ill. The diaphragm 23 andthe plate 25 which supports it arepresseddowm wardly by a spring 26 mounted within the cap 24.

The tension on the spring 26 is determined by adjustment of the setscrews 21, as will be seen fin Fig. 3.

I upper portion of chamber 30 and is pressed in ply line I I from acompressed oxygen tank. This supply line communicates through a channelii of an internal-frame memberwith a primary valve. This primary valveincludes a valve with its end portion pressing upwardly against From theunderside of the plate 25 and .dia-

V phragm 23 there extends a valve opening stem 28.

The lower end of the valve opening stem 28 presses against the upperface of the valve seat II with a pressure determined by the pressurewithin the compartment 2| and the action of the spring 26. It will beunderstood that the construction of the stem 28 is such that oxygen maypass about it-in issuing from .the valve;

Adjacent the primary valve chamber I3 is a secondaryvalve chamber 30,the latter communieating with the chamber 2| through the vent 3|.

A valve stem 32 extends downwardly from the downwardly biased positionby means of a spring 33 The lower end of stem 32 is provided with avalve seat 34 which bears against the port end of the lower valve sleeve35. It will be seenthat this valve is similar in construction to thecons'truction of the primary valve except that it is in invertedposition. The valve seat 34 presses downwardly against the open port ofsleeve 3 to prevent passage of oxygen through the valve. nislodgement orthe seat 34 allows oxygen to pass from the chamber 2|, through channel3|. about seat 34 and through the member 35 to chamber 22. valve openingrod ll similar to the stem 28 is positioned within the member 35 thevalve seat 34. The rod 36 acts against the pressure of the oxygen inchamber 2! and against the action of the spring 33. The extent of thedislodgement of the seat 34 therefore depends upon the upward pressureof the rod 36 and this in turn determines the amount of oxygen pass-'ing through the valve.

The lower portion of chamber 22 is closed by a rigid partition 31through which the lower end of the rod 36 extends. On the upper side ofthe partition 31 is mounted a Venturi-like cap member 38. This 'capmember opens on its underside beneath the partition member 31 and indirect communication with the aneroid chamber 39. The upper portion ofthe cap 38 is of bullet shape and contains openings 40. Surrounding thecap 38 and slightly spaced therefrom is a sleeve 4|. The sleeve 4|communicates with an oxygen dispensing line 42. Line 42 normally willextend adjacent the occupants of the plane and will be supplied with aplurality of individual dispensing units 43. Those dispensing units 43which are not in use will be closed by a suitable valve.

Below the housing I is a secondary aneroid housing 44 which is shownscrewed into a flange 45 on the housing I0, a suitable sealing ring 46being employed to provide a pressure-tight connection. Extending acrossthe housing 44 in a plane spaced somewhat below the partition 31 is apartial partition 41 which has a central opening across which extends aflexible pressuretight diaphragm 48. Partition 31, partition 41,diaphragm 48 and diaphragm 52 form the aneroid compartment 39, and itwill be noted that this compartment 39 is not open to the atmosphere.

Within the compartment 39 is positioned an aneroid 49 which has an uppercoupling member 50. The member 50 has a central opening into which theconnection is rigidly fitted, the connection 5| also being attached to aflexible pressure-tight diaphragm 52 extending across the upraisedportion 53 of the partition 31. The lower end of the valve-actuatingstem 36 abuts the connection member 5|. Expansion of the aneroid 49 upona decrease in pressure in the chamber 39 causes the coupling 50 andconnection 5| to move upwardly, thereby pressing the' valve-actuatingstem 36 upwardly to release the valve seat 34 and to permit oxygen toflow through the valve mechanism. The amount of the oxygen flow releasedin this manner will depend upon the pressure within compartment 39.

The lower portion of aneroid 49 is provided with a coupling 54 whichengages the coupling 55 of the flexible diaphragm 48. Coupling 55 alsoextends downwardly into connection with a second aneroid 56 which ispositioned in the chamber 51 provided by housing 44, partial partition41, diaphragm 48, and a bottom insert 58. The lower portion of theaneroid 56 is rigidly connected by means of the extension 59 to thebottom of the housing as shown in Fig. 3. Compartment 51 is open to theatmosphere through the vents 60 in the side of housing 44. The rigidconnection provided by the member 59 beneath the aneroid 56 results inthe vertical rise and fall of both the aneroids 49 and 56 to effectivelyoperate the .valve opening stem 36. The aneroid 56 operates directly inaccordance with the atmospheric pressure while aneroid 49 operatesindependently of atmospheric pressure.

Below the bottom member 58 is an indicating and adjustment housing 63which is provided with four-corner flanges 64. The flanges 64 extendupwardly in the manner shown in Fig. 4 and are rigidly connected toflanges 65 on the housing In by means of the bolts 66. The housing 63also carries an extension 61 through which is mounted the rotatableshaft 68. On the outer end ofv the shaft 68 is provided a hand screw 69and on the inner end of the shaft is provided a gear 10 which mesheswith the gear 62 of the bottom member 58, as shown in Fig. 3; Thehousing 63 is rigidly attached to the housing l0 and rotation of thehand screw 69 causes rotation of the bottom member 58 through gear 62 toprovide for the vertical adjustment of the bottom member. Since thebottom 58 is rigidly connected to the lower portion of the atmosphericaneroid 56 by means of the connection 59, raising the bottom member 58will result in the more effective operation of the aneroid with respectto raising the valve lifting stem 36.

Attached to the underside of the bottom member 58 is a flexible metallicstrip 1| which has a dial portion 12 positioned adjacent the opening 13of the partition member 14. The dial portion 12 is graduated in terms ofaltitude in such a manner as to show the minimum altitude at which theaneroid 56 will effect operation of the valve releasing stem 36. Thus,the hand adjustment screw 69 may be regulated to initiate the oxygenrelease at an altitude of 10,000 feet or 12,000 feet, as will beindicated to the operator by the member 12 which rotates with it. Sincethe aneroid 56 is open to the atmosphere through ports 68 it exerts avalve releasing action which is directly dependent upon the altitude.

a, The bottom 580i compartment 51 is screwed "into the lower end ofhousing 44 by means of The housing 63 is provided with a sight'glass 15which may be retained in position by means of a ring 16.

In Figs. 1 and 3 there is shown an indicating hand 16 which operatesabout graduations on the partition 14. This indicating hand may beoperatively connected through conventional mechanism (not shown) forindicating the pressure in the oxygen supply tanks.

In operation, the oxygenfrom supply line passes through channel l2 andthe primary valve and into compartment 2| where there is maintained apredetermined superatmospheric pressure. From compartment 2| the oxygenpasses through port 3| and the secondary valve and into compartment 22.From compartment 22 the oxygen passes through the sleeve 4| and into theoxygen dispensing line or manifold 42.

The amount of oxygen released from the manifold 42 will depend upon thenumber of the individual units 43 which are open and to some extent uponthe differential pressure between the manifold and the atmosphere. Thatis, as higher altitudes are reached, the resulting increaseddifferential will cause increased flow through the units, but theabsolute pressure in the manifold will remain unchanged. With increasedconsumption of oxygen there will be-an increased flow of oxygen throughthe sleeve 4|. This flow of oxygen past openings 46 of member 38 causesa decrease in pressure in the chamber 39 which causes an expansion ofthe aneroid 49, whereby the valve-actuating stem 36 is pressed upwardlyan increasing amount to release further oxygen from'the chamber 2f|. Asthe pressure within chamber 2| decreases the valve-actuating stem 28 ispressed downwardly against the valve seat l1 and the latter is pushedinto opened position sumciently to allow the passage of oxygen into thechamber 2| through the channels l2. Restoration, of the predeterminedpressure within primary chamber 2| insures adequate flow of oxygen fromthis chamber through the secondary valve and into the secondary chamber22.

Thus, if an additional unit 43 is opened there will result an increasedflow of oxygen to maintain the supply at the proper amount. This properamount will be the same for'each of the units regardless of the numberof units in operation. Since the dispensing units 43 have the same sizedispensing orifices, the controlled 'oxygen pressure insures the sameflow through each dispensing unit regardless of the number of users. Ifall of the units 43 are in operation the relatively rapid flow of oxygenthrough the sleeve 4! and into the outlet conduit 42 will produce such apressure condition within the chamber 39 as to provide the-same unitflow of oxygen for each of the members 43 as whereonly one or two ofsuch units are in operation. l

a primary pressure compartment, means forestablishing and maintaining apredetermined pressure in said primary pressure compartment,

a secondary pressure compartment, a valve between said compartments,means sealed from atmospheric pressure and responsive to a decrease inpressure in said secondary compartment for opening said valve, and ananeroid subject to atmospheric pressure for augmenting the action ofsaid last named means.

i 2. A device. of the type described, comprising actuated by saidaneroid for opening said valve,

Inlet line H is under the greatest pressure within the device. Thechamber 2| is under less pressure than the supply line H and the chamber22 is under less pressure than the chamber 2|, thereby providing athree-stage pressure mechanism.

Augmenting the action of the primary aneroid 49 is the action of thesecondary atmospheric aneroid 56. Regardless of the action of theaneroid 49, which compensates for the number of users by maintaining acontrolled absolute pressure in chamber 22, the aneroid 56 will supandan atmospheric aneroid augmenting the action of said first namedaneroid.

, 3. A'device of the type described, comprising a primary pressurecompartment, a secondary pressure compartment, means for maintaining apredetermined pressure in said primary pressure compartment, a valvebetween said primary pressure compartment and said secondary'pressurecompartment, a primary aneroid compartment the manifold and theatmosphere even without the action of the atmospheric aneroid, this in-,crease is less than consumption requirements. The action of theatmospheric aneroid, then, is to boost the basic absolute pressureestablished by the primary aneroid so as to supply this de-.

, ficiency. By maintaining in the manifold the independent ofatmospheric pressure, an outlet compartment to said outlet line, aprimary aneroid in said primary aneroid compartment, connecting meansbetween said aneroid and said valve, a secondary aneroid compartmentexposed to atmospheric pressure, a secondary aneroid in said last namedcompartment, connecting means between said aneroids whereby the actionof said primary aneroid is augmented by the action of said secondaryaneroid, and means for adjusting the position of said secondary aneroid.

4. In a device of the type described, a primary pressure chamber havinga flexible diaphragm.

a secondary compartment free from atmospheric;

pressure, a secondary valve, a secondary responsive means contained insaid secondary compartment in actuating relationship with said sec-.ondary valve, a flexible seal for sealing said secsive means.

- PAUL F. MEYN,

